1. The Field of the Invention
The present invention relates to designs and methods of modular foundation construction for bridges, piers, homes, or other structures that may incorporate a foundation. In particular, the present invention provides designs and methods of modular foundation construction such that an engineer may fabricate a portion of the foundation offsite, transport the fabricated portions to the construction site, and assemble the fabricated portions to construct the foundation for the desired structure.
2. The Relevant Technology
Many engineers today use some form of modular construction. In modular construction, an engineer may fabricate some portion of the structure offsite and then transport the fabricated portions to the construction site to be assembled. For example, in bridge construction, an engineer may fabricate the superstructure span portions offsite (such as pre-stressed concrete girders or pre-fabricated steel girders), and then assemble the fabricated portions at the construction site in order to speed construction and lower costs. Similarly, in building or home construction, an engineer may fabricate beams or columns offsite and subsequently erect the beams or columns onsite in the construction process of the building or home. In most cases, the construction industry recognizes the time and money saving benefits of minimizing the construction onsite by using modular techniques.
In contrast to the above discussion, the foundation is one portion of a typical structure that remains predominantly constructed onsite. Due to the difficulties in using modular techniques in the foundation construction process, modular construction progress in the overall construction of structures has been hampered. Given that typical foundation construction is not modular, the benefit gained from using other modular techniques to construct the remaining structure is diminished.
In particular, an engineer may spend weeks or even months constructing a typical cast-in-place foundation onsite. For example, a typical cast-in-place foundation may include a plurality of piles that an engineer drives into ground. The engineer may then construct a massive cast-in-place concrete cap to join the piles together, and to create an interface to join the foundation to the supported structure. Due to the time, effort, and materials an engineer may use to construct the cap, the construction of the entire structure may be slower, as well as more expensive.
Typical foundation designs and construction methods provide several challenges that tend to impede the modularization of foundation construction. One such challenge, for example, is the large size and heavy weight of the various foundation portions. In particular, the foundation cap may be a large and heavy, thus making it difficult to transport, and even more difficult to properly place during an assembly process. Thus, given the size and weight of typical foundation portions, a modular foundation construction may not be possible.
In addition to size and weight constraints, the tolerances between the various foundation portions may impede a modular foundation construction process. For example, and as discussed above, typical foundations include piles that an engineer may drive into the ground. During the pile driving process, the pile may move laterally with respect to an intended final position. In particular, during the pile driving process, a pile may “walk” because of soil irregularities or other uncontrollable factors. These deviations in tolerances with the final location of piles make it difficult for an engineer to anticipate the final dimensions, and thus impede an engineer's ability to prefabricate other portions of the foundation.
Mover, typical foundation components may not provide an efficient load path. For example, cast-in-place caps may result in a load path from the columns, through the cap, and subsequently into the plurality of piles. Engineers, however, may be impeded from constructing a foundation with a more efficient load path due to the limitations as discussed above. In particular, because a cast-in-place cap is designed to join the plurality of piles, it inherently also covers the piles causing the load path to be distributed through the cast-in-place cap, before being distributed to the piles.